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PNP Darlington power transistor

TIP127 Working Principle

Learn how TIP127 works with an illustrated explanation and practical readings.

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TIP127 at a glance

Follow the labeled connections and functional stages

TIP127 working principle: illustrated functional stages, basic circuit and connections
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How it works

3 stages · Explore one step at a time

Step 1 / 3

Sink base current

Pull the first PNP base below emitter through the resistor.

Step 2 / 3

Drive the second stage

The first transistor drives the second; their collectors are common.

Step 3 / 3

Return to off

Return base to emitter voltage and allow internal charge to discharge.

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